(1) Field of the Invention
The invention relates to a measuring method and system, and more particularly to a method and system for measuring a thickness of a thin film that can measure the thickness of a coated film in a real-time manner during a manufacturing process.
(2) Description of the Prior Art
Manufacturing processes for coating thin films have been widely applied to produce optical components, low-emissivity films and glasses, and various elements in the semiconductor industry. In these coating processes, control upon the thickness of the thin film is particularly important to the quality of the products. By having a process for coating an anti-reflection film on an optical head as an example, precision on the thickness of the coated film plays a critical role in the performance of anti-reflection. Further, by having a process for coating a low-emissivity film, the thickness of the coated film is one of key reasons that determine performance in heat insulation. Thus, the topic of monitoring the change in thickness of the thin film in a real-time manner during the manufacturing process so as for locating accurate timing to adjust process parameters, for stabilizing manufacturing quality and for varying purposely product's properties is definitely crucial to the art.
Generally speaking, among various methods for measuring the thickness of the thin film, a destructive detecting method and a numerical fitting method are usually seen. The destructive detecting method for measuring the thickness of the thin film can't be applied to measure the real-time thickness of the film while the coating process is under way. On the other hand, the numerical fitting method is used to compute the thickness of the coated film. However, since the computation involves the recursive iteration, plenty of calculation time would be needed, and also this method can't be applied effectively to measure or even monitor the thickness of the coating film in a real-time manner.
Thus, a method and system for measuring a thickness of a thin film that can monitor the thickness of the film in a real-time manner, while the coating process is under way, is definitely needed and welcome in the art.